Heretofore, mass PVC resin, or polymers thereof, that is resin produced in the absence of any emulsifiers or solvents contained a distribution of PVC particles, that is generally a distribution of so called "normal-sized" particles typically ranging in size from about 75 microns to about 425 microns and approximately from 1% or 2% to about 10% by weight of so called "fine-sized" particles smaller than 75 microns and usually smaller than 45 microns. Heretofore, separation of such fine particles from the produced resin blend was not known. Conventional techniques such as screening were unsuitable since the screens clogged. Static electricity build up in the fines also created separation problems.
U.S. Pat. No. 3,522,227 to Thomas, et al, relates to the production of mass PVC resins.
U.S. Pat. No. 4,198,376 to Francis Fournel, et al, relates to a vertical autoclave for producing mass PVC resin.
U.S. Pat. No. 4,257,880 to Jones relates to a centrifugal air classifying apparatus.